1. Field of the Invention
The subject invention relates to ablation catheters, and more particularly, to a small diameter steerable ablation catheter for performing renal denervation procedures through the renal artery of a patient.
2. Description of Related Art
Renal denervation is a minimally invasive, endovascular catheter based procedure using radiofrequency ablation aimed at treating resistant hypertension caused by narrowing of one or both renal arteries. By applying radiofrequency pulses to the renal arteries, the nerves in the vascular wall (adventitia layer) can be denervated. This causes reduction of renal sympathetic afferent and efferent activity and decreased blood pressure.
Generally, ablating the renal artery is done by heat through radiofrequency (RF) ablation, microwave ablation, irrigated heat ablation or cryoablation. The ablation of the renal artery is commonly performed through the femoral vein, which can cause substantial bleeding. Other options include access through the renal artery, which limits the diameter of the catheter systems.
Currently ablation catheters offered are either unipolar, which take substantial time to perform effective ablation of the renal artery, or are cage form catheters, which have several electrodes configured in a cage form, or are multiple ablation electrodes configured on an inflatable balloon.
All current multi-electrode systems, therefore, have a certain disadvantage in that they are relatively large in diameter (7 F or larger) and are often difficult to position in the renal artery, requiring the use of a fixed curve or steerable renal denervation catheter. The combination of the larger catheter diameter plus the use of a renal denervation catheter results in a system that is approximately 8 F or larger. Such large diameters are not desirable for either femoral placement due to large bleeding and recovery times or renal placement.
Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for a catheter-based ablation system that allows for improved access through the renal artery. There also remains a need in the art for such a system that is easy to make and use. The present disclosure provides a solution for these problems.